Also worth pointing out that if you have an music library that is 100% Classical, or have only a tiny amount of non-Classical, then I think the no-brainer is just option 2 where by default we just immediately enable all albums with the expanded 'classical' data fields. For the handful of non-Classical albums you have, okay, you might get the Composer info listed more which may or may not be useful to you, that metadata could actually be edited and deleted if it was an annoyance.
It becomes more of a challenge with a large library where the balance is more 50:50 between Classical and non-Classical.
So let me put this another way with a more simple question; for the Classical users here with a keen interest in this Classical Mode, would you say that over 75% of your library is Classical?